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Module Ida_bbd

module Ida_bbd: sig .. end

Parallel band-block-diagonal preconditioners for IDA (requires MPI).

type parallel_session = (Nvector_parallel.data, Nvector_parallel.kind) Ida.session

Alias for sessions based on parallel nvectors.

type parallel_preconditioner = (Nvector_parallel.data, Nvector_parallel.kind) Ida.Spils.preconditioner

Alias for preconditioners based on parallel nvectors.

type bandwidths = IdaBbdTypes.bandwidths = {
   mudq : int; (*

Upper half-bandwidth for the difference quotient Jacobian approximation.

*)
   mldq : int; (*

Lower half-bandwidth for the difference quotient Jacobian approximation.

*)
   mukeep : int; (*

Upper half-bandwidth for the retained banded approximate Jacobian block.

*)
   mlkeep : int; (*

Lower half-bandwidth for the retained banded approximate Jacobian block.

*)
}

The bandwidths for the difference quotient Jacobian operation.

type local_fn = float ->
       Nvector_parallel.data ->
       Nvector_parallel.data -> Nvector_parallel.data -> unit

Approximates the right-hand side function using local computations only. In the call gloc t y y' r, t is the independent variable (time), y is the dependent variable vector, y' is the derivative vector, and r is the output vector to fill with the computed residual.

Raising Sundials.RecoverableFailure signals a recoverable error. Other exceptions signal unrecoverable errors.

type comm_fn = float -> Nvector_parallel.data -> Nvector_parallel.data -> unit

Functions that perform the interprocess communication necessary for the execution of Ida_bbd.local_fn. In the call cfn t y y', t is the independent variable (time), y is the dependent variable vector, and y' is the derivative vector.

Raising Sundials.RecoverableFailure signals a recoverable error. Other exceptions signal unrecoverable errors.

val prec_left : ?dqrely:float ->
       bandwidths ->
       ?comm:comm_fn -> local_fn -> parallel_preconditioner

Left preconditioning using the Parallel Band-Block-Diagonal module. The difference quotient operation is controlled by ?dqrely, which specifies the relative increment in components of y, and Ida_bbd.bandwidths.

val reinit : parallel_session -> ?dqrely:float -> int -> int -> unit

Reinitializes some BBD preconditioner parameters. In the call, reinit s ~dqrely:dqrely mudq mldq, dqrely is the relative increment in the components of y, and mudq and mldq are, respectively, the upper-half and lower-half bandwidths of the difference quotient Jacobian approximation.

val get_work_space : parallel_session -> int * int

Returns the sizes of the real and integer workspaces used by the BBD preconditioner.

val get_num_gfn_evals : parallel_session -> int

Returns the number of calls to the right-hand side function due to finite difference banded Jacobian approximation in the setup function.